- The keto diet requires you to avoid carbohydrates and eat lots of protein and healthy fats.
- Bananas, apples, legumes, and potatoes contain too much natural sugar to work with the keto diet.
- Other seemingly healthy foods to avoid include quinoa and soy products.
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While vegetables are usually considered healthy, not all veggies are welcome on the keto diet.
Root vegetables are high in fiber and somewhat high in carbs, which goes against the main principle of keto. However, it is possible to incorporate small portions of some lower carb root vegetables, such as carrots, onions, and beets, into your diet.
Other vegetables that grow below the ground — especially potatoes, sweet potatoes, and parsnips — contain enough carbohydrates to be counted as keto dealbreakers.
Legumes, which include any kind of bean, lentils, sugar snap peas, and peas, are staples of many healthy eating styles. Vegan and plant-based eaters may turn to legumes as alternative sources of protein.
However, legumes are not so compatible with the keto diet. While legumes are good for you, they're also high in carbs. Even the benefits of high fiber aren't enough to offset the carb intake.
This means peanut butter is off limits as well, because peanuts are considered a legume.
Quinoa is often referred to as a "superfood," as well as a healthier alternative to carbs like rice or other grains.
Still, it's too high in carbs for the keto diet and also has a high glycemic index. This means it takes longer to digest, which causes a slow rise in blood glucose and insulin levels. However, some dietitians would say quinoa is an option if you're on a modified version such as a targeted keto diet.
Bananas may be great for muscle recovery, reducing bloat, and calming an upset stomach, but they're on the list of foods you can't eat on the keto diet.
With 25g of carbs per 100g serving, bananas are too high in carbs. Even though they're a complex carbohydrate with major potassium content, they're not a good option if you want to achieve ketosis.
Most nuts are encouraged to be eaten on the keto diet, as they are high in natural fats and proteins. However, some nuts have too many carbs to support ketogenesis.
Cashews, chestnuts, and pistachios are considered too high in carbs for the keto diet.
In general, the sweeter a vegetable is, the more natural sugar it has. This means your favorite vegetables might not be the best options on the keto diet.
While some forms of squash are keto-approved, butternut squash is too high in glucose and carbs to make it a good fit.
Starchy vegetables, like potatoes, are a definite "no" for the keto diet — they simply have too many carbs. You should be avoiding potatoes completely if you're on the keto diet.
Other starchy vegetables to steer clear of include corn, yams, and sweet potatoes.
Grapes are not allowed on the keto diet. Not only are they particularly high in sugar, but they are almost all carbohydrates — so even a small bunch of grapes can easily slow down or even stop ketogenesis.
Unfortunately, the no-grape rule also means you can't have too much wine (or raisins) on the keto diet.
There are some protein bars out there that are great for the keto diet, but not all energy bars are created equal.
Many energy bars are highly processed and filled with things like vegetable oil, artificial sweeteners, and additives that can all mess with the ketogenic state.
In general, you should avoid packaged snacks unless they're specifically labeled as keto — and you should probably check the ingredients list just to be safe.
There are a lot of fruits that aren't keto-friendly, thanks to their sugar and carb content. Red apples stand out because of how much sugar they have.
If you really want an apple, you're better off with a yellow or a green one, which have less sugar. You should also limit the number of berries and citrus fruits you eat if you're following the keto diet.
Mangoes and other tropical fruits
It probably doesn't come as a surprise that many tropical fruits are not allowed on the keto diet — after all, they are super sweet.
Anyone following the keto diet should say goodbye to fruits like mangoes, papayas, bananas, and pineapples.
Dates are often a staple in healthy diets because they make a sweet snack that is also full of fiber and vitamins. But they're a little too sweet to be keto-friendly. They're high in sugar and should be avoided if you're committing to the keto diet.
If you're supposed to avoid most fruits on the keto diet, then it makes sense that fruit smoothies wouldn't be allowed either.
Fruit smoothies can be full of sugar and even artificial ingredients. Any smoothie you buy in a store is unlikely to be keto-friendly. If you want to make a smoothie at home, use Greek yogurt or avocados as a base and avoid adding too much fruit.
Although soy products are typically low-carb, some experts say tofu is not ideal for people on the keto diet.
Soy products are high in estrogen-like nutrients called phytoestrogens, which can affect hormone levels over time.
Additionally, many soy products are highly processed, which is a big keto no-no. Lastly, soy products are high in phytates, another soy-derived nutrient that can cause inflammation in the gut. For these reasons, experts recommend avoiding soy while on the keto diet.